Compact membrane module system for gas separation

Abstract

A device for separating a gas, such as air, into components, includes a plurality of modules, each module having one or more polymeric membranes capable of gas separation. A set of valves, pipes, and manifolds together arrange the modules in one of two possible configurations. In a first configuration, the modules are arranged in parallel. In a second configuration, the modules are divided into two groups which are arranged in series. The device can be switched from parallel to series, or from series to parallel, simply by changing the positions of a small number of valves, typically three valves. The device can therefore produce gas either of higher purity, or moderate purity, depending on the settings of the valves.

Description

CROSS-REFERENCE TO RELATED APPLICATION[0001]Priority is claimed from U.S. provisional patent application Ser. No. 62 / 586,308, filed Nov. 15, 2017, the entire disclosure of which is hereby incorporated by reference.BACKGROUND OF THE INVENTION[0002]The present invention relates to the separation of gas into components using polymeric membranes.[0003]It has been known to use a polymeric membrane to separate air into components. Various polymers have the property that they allow different gases to flow through, or permeate, the membrane, at different rates. A polymer used in air separation, for example, will pass oxygen and nitrogen at different rates. The gas that preferentially flows through the membrane wall is called the “permeate” gas, and the gas that tends not to flow through the membrane is called the “non-permeate” or “retentate” gas. The selectivity of the membrane is a measure of the degree to which the membrane allows one component, but not the other, to pass through.[0004]A...

AI Technical Summary

Benefits of technology

[0019]The present invention therefore saves substantial space and weight, by using a single group of modules, contained in a single housing, for both parallel and series operation.

[0021]The invention has the further object of reducing the volume occupied by a membrane module system, while maintaining the flexibility of the system to operate in either a series or parallel mode.

[0022]The invention has the further object of providing a membrane-based gas-separation system which can be easily configured to provide either a moderate purity product gas, or a high purity product gas, simply by changing the positions of a small number of valves.

[0023]The invention has the further object of reducing the weight of a membrane-based gas-separation system.

[0024]The invention has the further object of reducing the cost of acquisition and operation of a membrane-based gas-separation system.

[0025]The invention has the further object of facilitating the production of either moderate purity nitrogen, or high purity nitrogen, using a set of gas-separation membrane modules contained in a single housing.

Problems solved by technology

Moreover, the series arrangement typically occupies considerably more space than does the set of parallel modules, because of the need to provide distinct stages which are separate from each other, each stage having its own housing.

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